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0

In theory, no - nothing detectable, that is. As Olin said, there would be some more wind resistance with a longer line, but this wouldn't be a huge factor. The change in potential energy would be the same for both harnesses, because the change in height for both would be the same. Since the kinetic energy of the rider is originally from the original ...


0

Use a large and thick copper spoon. Put the spoon in the coffee for 3 seconds. Remove it and insert the spoon in your mouth. (beware it will be hot) Use the tongue and palate to cool spoon pushing hard. When the spoon is close to the temperature of your mouth (feels tepid) remove it and reinsert the spoon in the coffee by another 3 secondos plus 0.5 ...


0

Without seeing the full context of what he says, he is most likely saying this in the context of classical physics, and it is most likely that he is saying that in this physics, particle dynamics are described by second order differential equations. Thus, if we know the positions and velocities of all the particles at any one time, these data fully define ...


0

When people jump up, they don't disappear from the earth - they just move by a small amount. Any gravitational attraction there had been before will still be there. A quick bit of estimating: 7 billion people, each weighing 50 kg (some heavier people in the USA, but lots of children and malnourished adults elsewhere in the world...) - total mass ...


-1

Answer to this question is only by understanding and not proof. If the Universe is expanding then I say Yes, to that the Matter is also expanding. Explanation for this is, all the Matter is expanding means, even the scale to measure the Matter is also expanding. Consider a small Example: A rectangular wooden block is expanding, Measure the initial ...


0

It is estimated that the whole population has a mass $316$ million tons: $3.16\times 10^{11}$kg. Earth's mass is estimated to be (I want to take this approximation) $6\times10^{24}$kg. So, taking into account the answer from Chanto and the "insignificance" of the world population mass vs Earth's mass, you can say that the difference would be $0$.


0

First of all, you have to understand, that even though all these people jumped up from the earth's surface, they would still interact with the standing person (gravitationally). So, when you say, that earth's mass decreases, you're actually wrong.


26

You can check this yourself using this very long link which will give you a list of Hawking's work that has been published in refereed journals, ordered by the number of times they have been cited in other papers (a measure of how influential they are on other scientists). This is a way of providing at least some non-opinion based answer to this question. ...


26

The two largest contributions that come to mind are both in the realm of general relativity. The first is his contribution to the singularity theorems. These are purely general relativistic results (i.e. no quantum mechanics involved), and they mathematically prove that generically one expects to find singularities in spacetime. That is, except in somewhat ...



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